The 2014 M3 (F80) prototype which was spotted in Los Angeles this past weekend has made its way into the California Mojave Desert's Death Valley for high temperature testing.

With high temperature testing always comes the removal of some front end camouflage, necessary to increase the prototypes' air intake and cooling; which makes us the indirect beneficiaries of ever better looks at an exposed front end.

Yesterday's F80 M3 spy pics (some copied below) gave us the best idea yet of the lines and shape of the front end styling, and today's sighting adds to that by showing us some even more details - particular the lines of the front bumper air vents which could not be seen through the cloth covered front apron from yesterday's photos.

What it reveals is that although the top part of the bumper side air vents will resemble the 2013 M6 in its upward angle and existence of an extra fin (masked in these pics, but obvious when the cloth camoflage is pressed against the bumper), the bottom portion will differ. The bottom parts of the side air vents are now revealed to be even more aggressive than that on the M6, with more angles and dynamic shape. With this new view, the entire side air intake takes on an even more aggressive angular and flared look.

A closeup of the masked front bumper further confirms what's likely to be air curtain vents on the sides of the lower front bumper, but they remain covered by tape. The interior also shows a dark headliner and sunblinds (leather?), making this the most advanced prototype we've spotted yet.